1. Field of the Invention
This invention relates to the field of milking machine systems and more particularly concerns a system for providing a sanitizing flush of such milking machine.
2. Description of Prior Art
Maintenance of high levels of sanitation in milking of cows is important both for the quality of the milk obtained and for the health of the animals involved. With regard to the health of the cows a major problem is the wide incidence of mastitis, a disease which seriously degrades productivity of many milking herds. The present-day desire for total automation, pushing more and more cows through the barn, together with the indifference to health and longevity of individual animals, may actually reduce monetary return for the dairyman by perpetuating and increasing the costly mastitis disease.
It has been shown that mastitis is spread during milking, not only from quarter to quarter but also from cow to cow. Thus, sanitizing solutions are desirably applied to the milking machines and may also be applied to the cows. Systems presently in use are manually controlled. They are not automatic, not adequately timed, difficult and relatively time consuming to operate, and not commercially successful.
Electrical timing devices may be employed for control of a valve but such electrical apparatus is not desirable in the environment of the milking machine since it introduces insulation problems, shock hazards and added expense of installation and maintenance.
For timing of an operation by means of bleeding of a pressure chamber, small capillary-type restrictive orifices or passages have been employed to provide a restriction of the bleeding flow sufficient to obtain a desired delay interval. Small diameter capillary-type passages are difficult and costly to produce with adequate repeatability and precision of operation and further, are readily subject to malfunction because the smaller the passage, the more readily it is obstructed by foreign matter in the solution being handled.
Accordingly, it is an object of the present invention to provide for the flushing of a milking machine with improved efficiency, reliability and control, while eliminating or minimizing problems present in other sanitizing systems.